P2628

DTC P2628: Rear A/F Sensor (Bank 1, Sensor 1) LABEL Circuit High Voltage

NOTE: Information marked with an asterisk (*) applies to the front bank (Bank 2).

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on, then let it idle for 2 minutes.
4. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2628 and/or P2631* indicated?

YES - Go to step 5.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and at the ECM/PCM.

5. Turn the ignition switch OFF.
6. Jump the SCS line with the HDS.
7. Disconnect the A/F sensor (Sensor 1) 8P connector.
8. Disconnect ECM/PCM connector B (24P).




9. Connect A/F sensor (Sensor 1) 8P connector terminal No.4 to body ground with a jumper wire.




10. Check for continuity between ECM/PCM connector terminal B10 (B19)* and body ground.

Is there continuity?

YES - Go to step 11.

NO - Repair open in the wire between the ECM/PCM (B10 (B19)*) and the A/F sensor (Sensor 1), then go to step 15.

11. Remove the jumper wire from the A/F sensor (Sensor 1) 8P connector, then reconnect ECM/PCM connector B (24P).
12. Start the engine. Hold the engine speed at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on, then let it idle.




13. Measure voltage between ECM/PCM connector terminals B10 (B19)* and D10.

Is there about 5 V?

YES - Go to step 14.

NO - Go to step 21.

14. Replace the A/F sensor (Sensor 1).
15. Reconnect ECM/PCM connector B (24P), and the A/F sensor (Sensor 1) 8P connector.
16. Turn the ignition switch ON (II).
17. Reset the ECM/PCM with the HDS.
18. Do the ECM/PCM idle learn procedure.
19. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P2628 and/or P2631* is indicated, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 20.

20. Monitor the OBD STATUS for DTC P2628 and/or P2631* in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 18 and recheck.

21. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.
22. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P2628 and/or P2631* is indicated, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.